I-5, SR 99 closures to hamper Seattle traffic this weekend

Work on the Mercer corridor is one of several projects that will close busy lanes and roads this weekend in Seattle. seattlepi.com file photo

Basically if you live near downtown Seattle, the Mercer Street corridor or state Route 99, don’t leave your house this weekend. If you do, don’t leave in a car.

A combination of lane, ramp and road closures as well as downtown events might turn an otherwise easy trip into a difficult commute.

The Seattle Department of Transportation offers the following warnings to motorists this weekend:

I-5 Closures

10 p.m. Friday, March 21 to 5 a.m. Monday, March 24

The northbound Interstate 5 collector-distributor will be reduced to a single lane between I-90 and Madison Street for bridge expansion joint replacement.

Drivers on northbound I-5 will not be able to connect with ramps to James and Madison Streets, but can still use the South Dearborn Street off-ramp.

The South Dearborn Street on-ramp to northbound I-5 will be closed.

The northbound I-5 on-ramp from Edgar Martinez Drive South will be closed.

The ramp from westbound I-90 to northbound I-5 will be open, but severe backups are expected.

The northbound mainline lanes will not be affected other than higher than normal traffic volumes are expected.

8 a.m. to 6 p.m. Saturday, March 22 and Sunday, March 23

The Mercer Street on-ramps to north and southbound I-5 will be closed while crews working for the City of Seattle install traffic detection equipment.

SR 99 Closures

11 p.m. Friday, March 21 until 10 a.m. Saturday, March 22

All southbound lanes of SR 99 will be closed between Valley and Thomas Streets for setting of girders as part of the Mercer Corridor project.

Seattle via SR 99 will be directed to I-5 in north Seattle at 85th Street.

4:30 a.m. until 7 p.m. Saturday, March 22

All lanes of the Alaskan Way Viaduct will be closed between South Spokane Street and the Battery Street Tunnel for bridge inspection.

Mercer corridor work

11 p.m. Friday, March 21 to 6 p.m. Saturday, March 22

Eastbound Mercer Street will be fully closed to traffic between Fifth Avenue N and Dexter Avenue N. Traffic heading east towards I-5 from Queen Anne will be detoured to Fifth Avenue N to either Denny Way to access southbound I-5 at Yale Avenue or through downtown on Fifth Avenue N to access northbound or southbound I-5.

The sidewalk on Mercer Street will also be closed between Fifth Avenue N and Dexter Avenue N. Pedestrians will be detoured to Broad Street.

The I-5 off-ramps at Mercer Street, westbound Mercer Street, and Broad Street will remain open during this work.

First Hill

10 a.m. to 6 p.m. on Saturday, March 22 and Sunday, March 23

The intersection of Broadway and E Madison Street will be closed during work on overhead wires as part of the First Hill Streetcar project.

Meanwhile, the Northwest Women’s Show, which began Friday, will continue at the CenturyLink Field Event Center Saturday and Sunday.

Also taking place Sunday is the 28th-Annual Big Climb at the Columbia Center.

The city advises motorists to expect traffic and parking congestion in those areas during the events.